Applications: Milling Machine, Lathe, EDM, Grinder. Relative humidity: Less than 90%. Readout input signal: TTL square wave. Input signal frequency: Less than 5M Hz. 5µm (0.005mm/0.0002). Min resolution of DRO angle :0.0001/pulse. DRO Dimensions: 11.6″X6.7″X2.56. Linear Scale Interface: DB9(RS232). SDM 200 sets memory, power-off memory for 10years, circumference drilling, oblique line drilling, 1/2 centering. The simple R function. Chambering (applicable to: Milling machine, Boring machine). Tool conpensation (for lathe). Machining of oblique plane. Package Included : 1pc 3Axis DRO Digital Readout 3pc Linear Scale 450+500+1000MM (18″ + 20″ + 40) 1set Installation Accessories 1pc User Manual. FAQ: Q1 : are the length 100mm, 150mm, 200mm…. Answer : all are travel length , total length = Travel Length +140mm Q3 : if i need a scale like 255mm , can you offer it? Answer : Please contact ToAuto to get the video. Q5: Do you have Installation Manual? Answer : Yes, Please contact the customer service to get the video.